Date control for chronometers



Oct.- 10, 1944. F. E. MEYER 2,360,305

DATE CONTROL FOR CHRONOMETERS Filed Dec. 9, 1942 3 Sheets-Sheet 1 FIG. 3.

. INVENTOR.

FRANCIS E. MEYER Oct. 10, 1944. F. E. MEYER 2,360,305

DATE CONTROL FOR CHRONOMETERS Filed Dec. 9. 1942 3 s t ..s t 2 F! INVENTOR. 5 FRANCES E. MEYER BY M Oct. 10, 1944. F. E. MEYER 2,360,305

DATE CONTROL FOR CHRONOMETERS Filed 66- 1942v 3 Sheets-Sheet 3 FIG. 4.

FIG. 5.

INVENTOR. FRANCIS E. MEYER Patented Oct. 10, 1944 UNITED STATES PATENT OFFICE 2,360,305 DATE CONTROL FOR GHRONOMETERS Francis Edward Meyer, Strasburg, Pa., assignor to Hamilton Watch Company, Lancaster, Pa.

12 Claims.

This invention relates to an improvement in the type of timepiece provided with .a twentyfour hour dial and adapted to keep account of the civil date as well as the hour of the day.

It is especially adapted to be used with the specially designed chronometer used in transport aircraft or any aircraft designed for long sustained flights.

It is the object of the present invention to provide means by which the mechanism controlling the civil date is held in abeyance during the setting of the timepiece.

It is a further object to provide means for releasing the mechanism controlling the civil .date from its advancing mechanism.

It is a further object to provide means for advancing the civil date irrespective of the rotation of the timing mechanism.

It is a further object of the invention to provide means for automatically moving .to inoperative position, the mechanism controllin the civil date, upon operation of the time setting mechamsm.

It is a further object of the invention to provide mechanism, which upon operation of the stem for setting the timepiece will swing the civil date advancing mechanism out .of operative position.

It is a further object to provide a civil date advancing mechanism, operated by the timing mechanism which upon any change of the hands by the setting means will be automatically swung into an inoperative position.

It is a further object of the present invention to provide means for normally advancing the civil date, which upon use of the time settin mechanism will be swung to inoperative position and upon the completion of said setting operation will be returned to normal working position.

It is a still further object of the present invention to provide means which will automatically, with the movement of the setting stem, move the civil date indexing mechanism from normal operating position to inoperative position and upon return of said setting stem will again move the civil date indexing mechanism to normal operating position.

It is a still further object to provide means which will automatically upon the setting of the chronometer swing the civil date mechanism to inoperative position and upon return of the setting stem will return the civil date advancin mechanism to its former position without effecting any change in the date.

The invention is illustrated in the accompanying drawings in which:

Fig. 1 is a view of the dial of the chronometer to which the improvement isapplied.

Fig. 2 is a top plan of that necessary portion of the chronometer movement together with the improved civil date advancing mechanism and the means for swinging it to inoperative position.

Fig. 3 is a view on line 3--3 of Fig. 2 taken in the direction of the arrows.

.Fig. 4 is a view on line 4-4 of Fig. 2 taken in the direction of the arrows.

Fig. 5 is a view on line 55 of Fig. 2 taken in the direction of the arrows.

The invention is particularly designed for that type of chronometer, the dial l of which is shown in Fig. 1 and which is adapted to be used in aircraft flying long sustained flights.

The dial is divided into twenty-four divisions 2 so that one revolution marks a twentyfour hour day. Hands 3 and 4 mark the hours and minutes respectively on this twenty-four hour dial. The dial also has on its outer edge a scale graduated into sixty divisions which are here shown (for convenience) only in multiples of five. This scale 5 is used with a sweep second hand 6 which is actuated by push buttons as an ordinary stop watch. The chronometer is also furnished with a continuously moving second hand I and dial 8 which is designed primarily to show at a glance that the instrument is running; An elapsed time dial 9 graduated into twelve divisions as are the more famiilar dials is ordinarily set at zero and started by a push button at the beginning of a flight or any period, the duration of which should be timed. .It has the ordinary hour hand It! and minute hand H. A dial l2 with a second hand I3 is designed to work with the hands 10 and II to provide the seconds in the lapsed time movement. This hand together with hands It and H is returned to a zero position at will.

The improvement which is the subject of this invention is directed to the dial I4 which is graduated into thirty-one divisions to show through the hand l5 the civil date, and to the movement controlling the advancement of said hand [5.

The remaining Figures 2-5 show only those portions of the chronometer movement which control or effect the civil date, all unnecessary (to the civil date operation) levers, plates and wheels are omitted to render the essential parts less obstructed on the drawings.

Referring now to Figs. 25, the arbor I6 is the one on which the hand I is mounted and which is journaled in the civil date bridge |1 at I8 and the bridge l9 at 2|]. This arbor I5 is formed with an integral shoulder 2| which is tapered at 22 to reduce the friction. Resting upon the flat face of the shoulder 2| is an index Wheel 23 which is secured to the enlarged portion 24 of the shaft I5 by staking. Movement of this index wheel is, therefore, transmitted directly to hand |5 through the arbor 16.

The central arbor 25 carrying the hands 2, 3 and 3 is shown but partially, the hollow shafts on which the hands 2 and 3 are mounted are omitted together with other details which form no part of this invention. It is sufiicient toconsider the central arbor having a disc (which is the hour wheel) 26 carrying a pin 21 projecting from its surface. forward semi-circular shoulder 28, the fiat edge 29 of which is in line with the radius of the disc 26, for reasons hereinafter disclosed.

A Y-shaped indexing lever 3|] is pivoted at 3| on the screw 32 held by bridge l1 and is formed along the right arm of the Y with a straight portion 33 adapted to be engaged by the forward semi-circular portion 28 of the pin 21 on its annular path. Movement of the disc 26 presses the pin 21 against the straight portion 33 which is forced in a circular path about the pivot 3| until the extreme upper edge 34 of the flat portion reaches the edge of the radial cut 29. The left arm of Y-shaped indexing lever 30 is extended to form the support 35 which terminates in the ear 36 to which a coil spring 31 is attached.

Pivoted at 38 to the support 35 is a pawl 39 engaging the indexing wheel 23. This pawl is formed with an upstanding arm 45 and a pin 4| which passes through opening 42 of the support 35 and rests on flat spring 43 also held on the support 35 by screws 44. Movement of the disc 28 has swung the arm 30 about pivot 3| moving the pawl 31 from tooth 45 to tooth- 45 of the indexing wheel 23. When upon further movement of the disc 26 the edge 34 of the Y-shaped arm clears the semi-circular upstanding portion of the pin, the radial cut allows the edge to clear and the spring 31 to pull the lever 30 clockwise thus advancing the indexing wheel one notch, turning the hand l5 another division or day. This happens once every twenty-four hours or upon movement of the hand 3 past the twenty-fourth division. In aircraft crossing time-changes in its flight it is necessary to move the hands forward or backward to indicate the proper time. As it is considered harmful to the delicate mechanism of a chronometer to move the hands counter-clockwise they are advanced twenty-three hours to retard the time one hour. This change or any similar movement of the hands which moves the hand 3 past the twentyfourth division causes the movement of the indexing wheel 23 and advances the civil date, causing resetting of the civil date or using the wrong date. As this may be necessary several times on a sustained flight, the inconvenience of resetting the civil date occurs several times also. The improvement to which this invention is directed is the mechanism which will automatically, with the setting of the hands 3 and 4, move the entire civil date mechanism into inoperative position. v

The stem used in winding and setting the Watch is shown at 41 with the gear 48 engaging the winding wheel 49 in one position and the setting wheel,5|l when in its pulled out position. A

This pin is formed with a cam 5| is formed on the stem 41 and engages the lever 52 to swing said lever about its pivot 53. This lever 52 is mounted on the hub 54, which of course forms the pivot 53, and is securely held to the cam surface by a support 55 which overlies and bears against the surface of the lever 52 at 56. A pin 51 carried on the lever 52 serves to transmit the motion of said lever to a disengaging lever 58.

Disengaging lever 58 is secured by pressing the hole therein over a polysided arbor at 59 to an arbor 60 which is journaled at BI and 62. A continuation of lever 58 is also secured as at 59 to said arbor at 63 and extends in the plane of pawl 39 which it is designed to operate. The arbor provides the necessary change in level to bring the camming action into the plane of the civil date indexing wheel. Carried on the extreme end of the lever 58 is an upstanding pin 64 while the other end of the lever is formed with a foot portion 65 contacting the pin 51. A spring 56 bears against the disengaging lever 58 at 61 to maintain contact at all times between the foot portion 35 and the pin 51.

The operation of the disengaging mechanism is such that as the stem 41 is pulled out in the normal setting operation, the cam 5| will engage the lever 52 and through the pin 51 and the foot portion 65 swings the disengaging lever 58 together with its arbor 65 to move the extreme end of said lever 58 together with its pin 64 in a counter-clockwise direction (Fig. 2). Thismovement causes the pin 64 to engage the upstanding arm 40 of the pawl, pivot the pawl about its pivot 38 and swing upward from the indexing wheel tooth 45. Continued movement of said lever causes the pin 4| to be forced against the restraint of spring 43 against the sides of hole 42 which will cause the motion to be transmitted to the Y-shaped lever 3iiand remove the portion 33 from the annular path of the pin 21, the whole mechanism taking the position of the dotted lines in Fig. 2. Thus the mechanism for advancing the civil date is swung out of operative position automatically during the setting of the hands. When the stem is returned to normal or winding position the spring 66 forcing the lever 58 in a clockwise direction (Fig. 2) maintains the foot portion 65 in contact with the pin 51 and thus holds the lever 52 against the cam 5|. This sup- .ports the pawl in raised position until it is over the tooth 45 and further movement of the lever 58 clears the arm 46 and allows the small spring 43 to return the pawl. This brings the pawl into the same tooth from which it was withdrawn and consequently does not effect the civil date indexing wheel.

A further mechanism associated with the civil date is the advancing L-lever 6B which is pivotally supported in a recess 69 of the bridge H by the screw 10 (Fig. 2). The advancing L-shaped lever has upstanding pins 1| and 12 mounted thereon and the short leg of the. lever carries a spring finger 13 held by screws 14. The pin 12 serves as a terminal for the coil spring 15 which is anchored to a similar pin 16 on the bridge 11 and tends to force the lever 68 about its pivot in a counter-clockwise direction, thus normally keeping the spring finger from contact with the teeth of the indexing wheel 23. A slide 18 engages the pin 1| and is actuated by cam 19 acting against the upturned edge of said slide. The cam is connected to a push rod (not shown) which extends beyond the case and is operated by the finger. A slight depression of said rod moves the cam which shoves the slide against the pin H swinging the advancing lever in a clockwise direction, engaging the spring finger with a tooth of the indexing wheel and advancing the civil date one day for each push of the rod. Thus the civil date may be manually set should such action be desired.

, An index wheel spring pawl 81 secured in the recess 69 at 82 steadies the action of the index wheel and prevents undesired advancing of said wheel. A pin 83 serves as a stop for the Yshaped lever 30 holding it in a .position to be engaged by the pin 21 once every revolution of the disc 25.

This civil date mechanism which can be swung out of operative position automatically with the setting of the watch reduces handling of the chronometer as it would otherwise be necessary to operate the slide twenty-nine or thirty times each time the hands 3 and 4 were set, a condition much to be desired.

What is claimed is:

1. In a chronometer, a civil date mechanism comprising an indexing wheel, means for advancing said wheel in accordance with the revolutions of the chronometer, means for setting the chrnometer and means actuated by said setting means for swinging said indexing wheel advancing means to inoperative position.

2. In a chronometer, a civil date mechanism comprising an indexing wheel, means for advancing said wheel in accordance with the revolutions of the chronometer, means for setting said chronometer, means actuated by said setting means for swinging said indexing wheel advancing means to inoperative position and means for returning said indexing wheel advancing means to the position held previous to the setting operation.

3. In a chronometer, a civil date mechanism comprising an indexing wheel, means for advancing said wheel in accordance with the revolutions of said chronometer, means for setting said chronometer, means actuated by said setting means for swinging the index wheel advancing means to inoperative position and means for holding said indexing wheel in position.

4. In a chronometer, a civil date mechanism comprising an indexing wheel, a lever pivotally supported in the path of the hour wheel of the chronometer and movable in accordance with the revolution of said wheel, a pawl carried by said lever and engaging said index wheel, a setting mechanism and means actuated by said setting mechanism for swinging said lever and pawl into inoperative position.

5. In a chronometer, a pin carried in an annular path by said chronometer movement, an indexing wheel for advancing the civil date of said chronometer, means actuated by said pin for advancing said indexing wheel, a setting mechanism and means actuated by said setting mechanism for swinging said indexing wheel advancing means to inoperative position.

6. In a chronometer, a pin carried in an annular path by said chronometer movement, an indexing wheel for advancing the civil date of said chronometer, means actuated by said pin for advancing said indexing wheel, a setting mechanism for said chronometer and meansactuated by said setting mechanism for swinging said indexing wheel advancing means to inoperative position.

7. In a chronometer, a pin carried in an annular path by said chronometer movement, means actuated by said pin for advancing the civil date of said chronometer, a setting mechanism and means actuated by said setting mechanism to swing said civil date advancing means to inoperative position.

8. In a chronometer, a moving pin carried in an annular path by said chronometer movement, a civil date advancing mechanism comprising an indexing wheel having ratchet teeth, a Y-shaped lever having a short arm normally in the path of said moving pin and a long arm extending above the indexing wheel, a pawl carried on said long arm engaging the teeth of said indexing wheel, a lever moving said pawl out of engagement with said teeth, further movement of said lever swinging said Y-shaped lever from the path of said moving pin and means for operating said lever.

9. In a chronometer, a moving pin carried in an annular path by said chronometer movement, a civil date advancing mechanism comprising an indexing wheel having ratchet teeth, a Y-shaped lever having a short arm normally in the path of said moving pin and a long arm extending above the indexing wheel, a pawl carried on said long arm engaging the teeth of said indexing wheel, a lever moving said pawl out of engagement with said teeth, further movement of said lever swinging said Y-shaped lever from the path of said moving pin, means for setting the hands of the chronometer, and means controlled by the action of the chronometer setting means for operating said lever.

10. In a chronometer, a moving pin carried in an annular path by said chronometer, a civil date advancing mechanism comprising an indexing wheel having ratchet teeth, a Y-shaped lever having a short arm normally in the path of said moving pin and a long arm extending above the indexing wheel, a pawl carried on said long arm engaging the teeth of said indexing wheel, a lever moving said pawl out of engagement with said teeth, further movement of said lever swinging said Y-shaped lever from the path of said moving pin, means actuated by movement of the setting stems for operating said lever and means actuated by the return of said setting stem for returning said civil date advancing mechanism to its former position.

11. In a chronometer, a civil date mechanism comprising an indexing wheel, means for advancing said wheel in accordance with the revolutions of the chronometer, means for setting the chronometer, means actuated by said setting means for swinging said indexing whee] advancing means to inoperative position, and means for returning said indexing wheel advancing means to normal working position.

12. In a chronometer a civil date mechanism comprising an indexing wheel, a pawl for advancing said wheel, a lever for pivotally supporting said pawl and actuated by the revolutions of the hour hand of the chronometer, a pivoted lever adapted to move said pawl about its pivot and out of engagement with said indexing wheel, a second pivoted lever engaging the first mentioned pivoted lever and a cam actuated by the setting means of the chronometer to swing said pawl into an inoperative position.

' FRANCIS EDWARD MEYER. 

